Common names: toothcarp (English), livebearer (English), olomina (Espanol), guatopote (Espanol)
Poeciliopsis latidens (Garman, 1895)
Lowland livebearer, Broad-toothed toothcarp
Moderately elongate, compressed; head small, flattened above, snout short, blunt, rounded; eye large, longer than snout; mouth rather wide; outer jaw teeth chisel shaped, hooked and strong, inner teeth in bands, commonly expanded near tip; dorsal I, 7; anal II, 8; tail rounded to straight; pelvic rays 7 & 8 distorted, converging or in contact at midlength; male sex organ a tube on left side formed by folded (but not twisted) anal fin rays, long (reaches to or nearly to the base of the tail fin) and slender; scales large, smooth, 28-30 along mid-side.
Yellow brown, darker on back; opercle and belly silvery; a series of 7-12 (5-14) short black bars and spots along the upper flank, 1-2 of those bars reaching to or nearly to top of back; sometimes round dark spots on lower body; a dark line along underside of tail base from anal fin to tail fin; base of dorsal and tail fins yellowish, rest of fins clear.
Size: grows to 5 cm in both sexes.
Habitat: freshwater streams and brackish lagoons
Depth: 0-2 m.
Eastern Gulf of California – Sonora to Nayarit.